Four-wheel drive-tractor



Patented Mar. 2, 1920.

2 SHEETS-SHEET D S STEWART FOUR WHEEL DRIVE TRACTOR.

APPLICATION FILED OCT. 22, 1918.

D. S. STEWART.

FOUR WHEEL DRIVE TRACTOR.

APPLICATION FILED OCT- 22, 1918.

1,332,579, v PatentedMar.2,1920.

2 SHEETS-SHEET 2- .525 W :mmmm

' a I I WWI l Wow y U N IT E D STATES PATlN T OFFICE. Davin s.s'rnwnn'r, or mreo, WISCONSIN, assronon r0 mneomcron co., or mlco,WISCONSIN, A conronerron' or wisco wsm.

FOUR-WHEEL DRIVE-TRACTOR.

Specification of Letters Patent. 7 Patent ed Mar, 2, 1920.

Application filed Octobgt 22, 1918. Serial No. 259,166.

To all whom it may concern:

Be it known that I, DAVID S. STEWART, a citizen of the United States,and resident of Antigo, in the county of Langlade and State ofWisconsin, have invented certain new and useful Improvements in Four-Wheel Drive-Tractors; and I do hereby declare that the following is afull, clear, and exact description thereof;

My invention relates to certain new and useful improvements in heavyduty motordriven trucks or tractors, and has for its primary objecttoprovide a simple, durable and economical truck of the above characterwherein the four wheels are positively driven through the medium ofsimple gear connections from the source of power.

Another object of the present invention is to provide a separatetransmission mechanism for each set of traction wheels and to providefor simultaneously operating the transmission mechanisms, whereby jerkymovements of the truck when being started are prevented.

A further object of the herein disclosed invention is to mount eachtraction wheel connection with the axle of the truck and capable ofbeing simultaneously operated to provide for the eflicient steering ofthe truck.

A still further object of this invention is to provide a novel manner ofcoupling the traction wheels with the motor or source of power withoutinterfering with the efficient operation of the steering knuckles andwhereby an increased amount of power is obtained.

With the above and other objects in view which will appear as thedescription proceeds, my invention resides in the novel construction,combination and arrangement of parts substantially as hereinafterdescribed, and more particularly defined by the appended claims, itbeing understood that such changes in the precise embodiment of theherein disclosed invention may be made as come within the scope of theclaims.

In the accompanying drawings I have illustrated one complete example of.the physical embodiment of my invention constructed according to thebest mode I have so far devised for the practical application of theprinciples thereof, in which:

Figure 1 represents atop plan view of a truck embodying the features ofmy invention with parts broken away and in section to more clearlyillustrate minor details of construction. v

Fig. 2 represents a view part in section and part in elevation and takentransversely through one end of the truck on the line 2-2 of Fig. 1.

Fig.- 3 represents a longitudinal sectional I view taken through one endof the truck on the line 33 of Fig. 1.

Fig. 4 represents a transverse sectional view taken through the sleeveof one of the steeriig knuckles on the line 44 of Fig. 2, an

Fig. 5 represents a diagrammatic view of the driving engine andtransmission mechanisms illustrating the manner of simultaneouslycontrolling the operation of the transmission meehamsms.

Referring by characters to the drawings, 1, 1, represents the side sillsof a rectangular main frame, to the intermediate portion of which isbolted an internal combustion engine or other suitable source of power2, having its crank shaft extended both rearwardly and forwardlytherefrom as at 3, and operatively connectin each end of said shaft withthe drive sha s 4, 4, which extend longitudinally of the frame andtoward each end thereof, are suitable transmission mechanisms, and, asthe transmission mechtion of'one will suffice for all.

The transmission mechanism consists primarily of a sleeve 5 fixed to theshaft 3 and having an internally toothed drum 6 projecting over andspaced from the inner end of shaft 4, a sleeve 5 fixed to the inner endof shaft 4 and formed with gear teeth 6 in line with the teeth of drum6, and idler gears 7, j ournale'd on the stub shafts carried by a plate8, connecting the gear 6 and 6 as best shown in Fig. 3. The plate 8 iscarried by a drum 9 rotatably mounted about drum 6 and has securedtherearound a suitable braking band 10 adapted to bind thereby saiddrum9 is a clutch 11 adapted to be fOl'tBd inwardly to engage a plate 12keyed to the sleeve 5, by means of pivoted arms or links13 coming intoengagement with a cone shaped member 14 carried by the operating lex er15 pivoted at 16 to a link 17 having its other end fixed to a lug 18.The brake band 10 is operated by means of a pivoted lever 19 provided atits inner end with a cam surface 20 adapted to, upon operation, impingeagainst and draw together the free ends of the brake band 10, the lever19 being connected to lever 15 by means of a link 21.

The transmission mechanism just described is of well known constructionhaving one speed forward, and one speed reverse and constitutes no partof the present invention. When the lever 15 and parts connectedtherewith are in the position depicted in Fig. 3 the motor is connectedup with shaft 4 to revolve the same forward, the drums 6 and 9 beingconnected by means of clutch 11 to drive shaft 4 direct, and when thelever 19 is in a position to the right of that depicted in Fig. 3. itsshaft 4 is being driven reverse to shaft3, the brake band retaining drum9 from revolution, clutch 11 bein free from (plate 12 and drum 6revolvin s eeve 5 an with it shaft 4 by means of idler ears 7 as will beobvious.

In or er to obtain the simultaneous operation of the two transmissions,one of the levers 15 has its lower end extended below pivot 16 as at 16'and has ivoted thereto a connecting rod or link 21 w 10h has ts otherconnected to the other operating lever 15 just above its pivot point 16whereby the simultaneous operation of the respective levers will beprocured as will be apparent to those skilled in the art to which aninvention of this character appertains.

The shaft 4 extends toward the end of the main frame and is journaled inbearing sleeves 22,formed in an enlargement or housing 23 providedintermediate the ends of a hollow axle 24. The main frame is carried bydownwardly bowed bracket bars 25 extending transversely between andsecured to the side sills 1 of the main frame, said bars being providedcentrally with bearings which receivethe bearing sleeves 22, saidsleeves being projected outwardly of the housing 23 to thus mount thebracket bars. J onrnaled in the hollow axle 24 is a shaft 26 having itsends extended beyond the ends thereof and carrying on its portion in thehousing 23 a worm gear wheel 27 in mesh with a worm ear 28 formed on theportion of shaft 4 in said housing 23.

Each end of the axle 24 has formed thereon a ,pair of spaced ears 29provided with verticallv alined apertures 30 in which ,are journaled thebushings 31 carried by the vertical sleeves 32 of the steering knucklesprovided with suitable stub axles 33 for j ournally mounting suitabletraction wheels 34, the bushings 31 being retained in the sleeves 32 bymeans of" suitable dowel or talzlered pins 34' as best shown in Figs. 2an 4.

J ournaled in each bushing 31 is a vertical shaft 35 having its endsextended beyond the ends of the said bushing and mounted on the upperend of said shaft is a small beveled gear 36 in mesh with a ring ormaster ear 37 fixed to the traction wheel 34, and xed to the lower endof said shaft 35 is a large beveled gear 38 meshing with a small beveledgear 39 fixed on the adjacent end of the shaft 26. Thus it will be seenthat power is transmitted through shaft 4 to shaft 26 by means of gears27 and 28 and to the traction wheels by means of gears 38 and 39, shaft35 and gears 36'and 37.

As will be readily seen by reference to Fig. 2, the steering knucklesare free to move between cars 29 without interfering with the operationof the driving mechanism and that through this manner of connecting thewheels 34 with the drive shaft 4, a powerful gearing is provided whichis such as to permit the use of the transmission mechanisms hereinbeforedescribed.

As best shown in Fig. 1 each steering knuckle is provided with an arm40, the opposed arms 40 being connected by means of a suitable rod 41and one of the steering knuckles at each end of thetruck being providedwith a second arm 40 from which leads a suitable rod 42 connected to acrank 43 of a steering rod 44 rovided with suitable operating gears 45 Wereby the simultaneous steering of all four wheels is provided. As'willbe obvious the usual hand wheel, not shown, is generally connected withgears 45 but that if desired the same may be connected with the enginein a suitable manner and with suitable controlling means to provide forthe operation thereof.

While in the present exemplification of my invention, I have illustratedthe same as dispensing with the usual differential, it will be readilyapparent that a suitable differential mechanism may be used withoutdeparting from the spirit of the invention.

I claim:

1. A. truck including a frame, front and rear axle housings, a drivewheel mechamsm carried by one of said housings, a pair of a'linedbushings carried by said axle housing and extending outwardly thereof,means for driving said wheel mechanism including a shaft extendinglongitudinally of the frame and traversing the housin and journaled, inthe bushings thereof, an a pairof pivot bearings carried by the adjacentend portion of the frame and mounted on the bushings of the adjacentaxle housing, said axle unit being otherwise free from connection withthe frame 2. A tractor including an elongated main wheel drive shafts,wheels driven by said 10 chassis, an engine mounted centrally of theshafts, and means for simultaneously operatchassis on the side sillsthereof, a variable ing said transmission mechanisms and clutchtransmission mechanism mounted on the side connections. sills of thechassis at each end of the engine, In testimony that I claim theforegoing a clutch connection between the shaft of the I have hereuntoset my hand at Antigo, in 15 engine and each transmission mechanism, athe county of Langlade and State of Wisdifl'erential mechanism connectedwith each consin. end of the chassis and including transverse DAVID S.STEWART.

